elf/tst-auditmod28.c

   1 /* Check the usability of <dlfcn.h> functions in audit modules.  Audit module.
   2    Copyright (C) 2022-2023 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <dlfcn.h>
  20 #include <first-versions.h>
  21 #include <gnu/lib-names.h>
  22 #include <link.h>
  23 #include <stdio.h>
  24 #include <string.h>
  25 #include <unistd.h>
  26
  27 #include <support/check.h>
  28 #include <support/xdlfcn.h>
  29
  30 unsigned int
  31 la_version (unsigned int current)
  32 {
  33   /* Exercise various <dlfcn.h> functions.  */
  34
  35   /* Check dlopen, dlsym, dlclose.   */
  36   void *handle = xdlopen (LIBM_SO, RTLD_LOCAL | RTLD_NOW);
  37   void *ptr = xdlsym (handle, "sincos");
  38   TEST_VERIFY (ptr != NULL);
  39   ptr = dlsym (handle, "SINCOS");
  40   TEST_VERIFY (ptr == NULL);
  41   const char *message = dlerror ();
  42   TEST_VERIFY (strstr (message, ": undefined symbol: SINCOS") != NULL);
  43   ptr = dlsym (handle, "SINCOS");
  44   TEST_VERIFY (ptr == NULL);
  45   xdlclose (handle);
  46   TEST_COMPARE_STRING (dlerror (), NULL);
  47
  48   handle = xdlopen (LIBC_SO, RTLD_LOCAL | RTLD_NOW | RTLD_NOLOAD);
  49
  50   /* Check dlvsym.  _exit is unlikely to gain another symbol
  51      version.  */
  52   TEST_VERIFY (xdlsym (handle, "_exit")
  53                == xdlvsym (handle, "_exit", FIRST_VERSION_libc__exit_STRING));
  54
  55   /* Check dlinfo.  */
  56   {
  57     void *handle2 = NULL;
  58     TEST_COMPARE (dlinfo (handle, RTLD_DI_LINKMAP, &handle2), 0);
  59     TEST_VERIFY (handle2 == handle);
  60   }
  61
  62   /* Check dladdr and dladdr1.  */
  63   Dl_info info = { };
  64   TEST_VERIFY (dladdr (&_exit, &info) != 0);
  65   if (strcmp (info.dli_sname, "_Exit") != 0) /* _Exit is an alias.  */
  66     TEST_COMPARE_STRING (info.dli_sname, "_exit");
  67   TEST_VERIFY (info.dli_saddr == &_exit);
  68   TEST_VERIFY (strstr (info.dli_fname, LIBC_SO));
  69   void *extra_info;
  70   memset (&info, 0, sizeof (info));
  71   TEST_VERIFY (dladdr1 (&_exit, &info, &extra_info, RTLD_DL_LINKMAP) != 0);
  72   TEST_VERIFY (extra_info == handle);
  73
  74   /* Verify that dlmopen creates a new namespace.  */
  75   void *dlmopen_handle = xdlmopen (LM_ID_NEWLM, LIBC_SO, RTLD_NOW);
  76   TEST_VERIFY (dlmopen_handle != handle);
  77   memset (&info, 0, sizeof (info));
  78   extra_info = NULL;
  79   ptr = xdlsym (dlmopen_handle, "_exit");
  80   TEST_VERIFY (dladdr1 (ptr, &info, &extra_info, RTLD_DL_LINKMAP) != 0);
  81   TEST_VERIFY (extra_info == dlmopen_handle);
  82   xdlclose (dlmopen_handle);
  83
  84   /* Terminate the process with an error state.  This does not happen
  85      automatically because the audit module state is not shared with
  86      the main program.  */
  87   if (support_record_failure_is_failed ())
  88     {
  89       fflush (stdout);
  90       fflush (stderr);
  91       _exit (1);
  92     }
  93
  94   return LAV_CURRENT;
  95 }
  96
  97 char *
  98 la_objsearch (const char *name, uintptr_t *cookie, unsigned int flag)
  99 {
 100   if (strcmp (name, "mapped to libc") == 0)
 101     return (char *) LIBC_SO;
 102   else
 103     return (char *) name;
 104 }